Nanjing Continental Electric explains the behavior and control of 5000W wind turbines (2)
Nanjing Oulu Electric Co., Ltd. is a high-tech enterprise specializing in R&D, production, sales and service of new energy power generation products and industrial automation control products. The main products are 5000W wind turbines , wind and solar hybrid controllers, controllers and inverters. , wind and solar hybrid communication base station monitoring and management system, inverter drive, servo drive, permanent magnet synchronous motor, electric vehicle motor controller, etc.; mainly serve the three major fields of new energy, energy saving and environmental protection, equipment manufacturing. Comprehensive product development and testing, advanced manufacturing equipment and testing instruments, strictly in accordance with standard operating practices, to ensure the stability and accuracy of product quality.
In recent years, in response to the government's policy of promoting from a manufacturing power to a manufacturing power, in-depth study and discussion of wind turbine operation behavior and system control theory, overcoming many difficulties and technical checkpoints, has established its own wind turbine system behavior and control theory, The software and hardware of the wind turbine control system have been developed and successfully applied to active control wind turbines with variable awards, steering and braking. This control system can also be applied to the largest wind turbines in the highest level, breaking through foreign technology. Blockade.
The following describes the behavior of the wind turbine, followed by the last (1)
Large wind turbines and small wind turbines have different operating trajectories and reaction speeds due to their different moments of inertia and erection height. Therefore, the characteristics of the wind and the operating behavior of the wind turbine and the response to the wind must be different. Speed has a complete understanding and understanding before it can make correct planning and judgment.
The wind is affected by the Boundary layer effect, the closer to the ground, the lower the wind speed and the greater the turbulence intensity. Large wind turbines have high erecting height and high wind speed and low turbulence intensity; small wind turbines have the opposite, low erection height, low wind speed and high turbulence intensity; NWP (Normal wind profile) in IEC 61400-1 V=Vhub (Z /Zhub)0.2, when the wind turbine reaches 10m/s (Class I) at 80m, the wind speed of the small wind turbine at 8m is only 6.3m/s (Class III). When the small wind turbine reaches 10m/s (Class I) at 8m, the large wind turbine has reached 16m/s at 80m, which has almost reached the condition of light typhoon. Therefore, the small wind turbine is not required to be Class due to the low erection height. I, because there are few opportunities, this is why AWEA, BWEA, Class NK and IEC will set Vdesign=1.4Vave=11m/s, so Vave=7.85m/s slightly exceeds Class III.
So the behavior of large wind turbines and small wind turbines is very different:
• Large wind turbines: large size, heavy weight, large moment of inertia, like a large truck, slow acceleration and deceleration, and because of the high height of the large wind frame, the wind speed is stable and small, so the speed changes slowly, so it is necessary to control the most. Better λ (TSR) means that the best Cp value is easier, so it is more efficient, up to 0.5 (Enercon E112).
• Small wind turbine: small size, light weight, small moment of inertia, like super-running, fast acceleration and deceleration, and because of the low height of the small wind frame, the wind speed changes greatly, so that the speed change is not easy to fix near a certain speed, so It is difficult to control the optimal λ=rω/V (TSR) meaning that the optimal Cp value (although the blade design can reach 0.45 or more), so the general efficiency is poor, and Cp can reach 0.35. In addition, because small wind turbines generally have no anemometer, that is, no wind speed data, λ cannot be calculated, so it is even less likely to achieve the best Cp.